Dissolution Profile of Tosufloxacin Tosylate in Biorelevant Bicarbonate Buffer Containing Sodium Chloride: Precipitation of Hemi-hydrochloride Salt at the Particle Surface.

ABSTRACT:

Purpose

The purpose of the present study was to investigate the dissolution profile of tosufloxacin tosylate monohydrate (TFLX TS) in biorelevant bicarbonate buffer (BCB). TFLX is a zwitterionic drug (pK_a: 5.8 and 8.7), formulated as tosylate salt to enhance its dissolution.

Methods

The dissolution profiles were measured in BCB or phosphate buffer (PPB) at pH 6.5 with buffer capacity (β) = 0.88 or 4.4 mM/pH, containing NaCl or Na₂SO₄ (I = 0.14 M). The residual particles were analyzed by powder X-ray diffraction. In a separate study, the particle surface of TFLX TS after contact with BCB was observed by scanning electron microscopy and real-time polarized light microscopy. The pH solubility profile of TFLX was measured using HCl and TS solutio

SUBMITTER: Okamoto N 

PROVIDER: S-EPMC12405044 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature